KR20200054286A - Transmission control methods, devices and systems - Google Patents

Abstract

The present application provides a transmission control method, wherein in the process of reassigning a first user plane function network element to a second user plane function network element, the session management function network element requests each session to be modified. To each anchor user plane function network element of the plurality of anchor user plane function network elements, each session modification request including information about the second user plane function network element; And directing only the first anchor user plane function network element in the plurality of anchor user plane function network elements to transmit the end marker, or transmitting the end marker only to the first anchor user plane function network element. This solution solves the packet loss problem of downlink data packets in a scenario of reallocating user plane functional network elements, thereby improving the user experience.

Description

Transmission control methods, devices and systems

The present invention relates to the field of communication technology, in particular transmission control methods, devices and systems.

In a fifth generation (5th-Generation, 5G) communication network, a data transmission path may be switched after a user equipment (UE) moves. For example, as illustrated in FIG. 1A, before the UE moves, the transmission path of downlink data is an anchor user plane function (UPF)-> source intermediate UPF (intermediate UPF, I-UPF)- > Source radio access network (RAN). After the UE moves, in the handover process, the transmission path of the downlink data packet (old path) is the anchor UPF-> source I-UPF-> source RAN-> target RAN (shown by dotted lines in the figure) ). After the handover is completed, the transmission path (new path) of the downlink data packet is the anchor UPF-> target I-UPF-> target RAN (shown as a solid line in the figure). Therefore, the downlink data packet individually reaches the target RAN on the new path and the old path.

To ensure that the downlink data packets are not out-of-order, the target RAN first sends downlink data packets to the UE on the previous path and then downlink data packets on the new path. Should be transmitted to the UE. A packet data unit (PDU) end marker per PDU session (abbreviated end marker) mechanism is used in the prior art. In this mechanism, the anchor UPF must send an end marker on the old path when the path is updated, and the end marker indicates that this is the last downlink data packet on the old path, and the subsequent downlink data packet will be transmitted on the new path. (indicate).

For a scenario of multiple transmission paths, the UE has multiple session branches, as shown in FIG. 1B. Before the UE moves, the session established using the source I-UPF may be offloaded. For example, the source I-UPF has two session branches. Branch 1 corresponds to the anchor UPF 1 and Branch 2 corresponds to the anchor UPF 2. When I-UPF reassignment occurs, there may be two cases. Case 1: Both branches are switched towards the target. Case 2: Only the primary branch (e.g., branch 1) is switched towards the target, and the secondary branch (e.g., branch 2) is not switched.

In one of the cases described above, for example, after branch 1 is switched and all data packets on branch 1 are transmitted, anchor UPF 1 transmits an end marker through the source RAN to the target RAN. After receiving the end marker, the target RAN considers that the transmission of the downlink data packet on the previous path ends, and starts to transmit the downlink data packet to the UE on the new path. However, transmission of a downlink data packet on branch 2 may not be completed. Since these data packets are received after the end markers are received, the target RAN discards these data packets directly. This results in data packet loss, reducing the user experience.

Embodiments of the present invention provide a transmission control method, apparatus and system.

According to a first aspect, an embodiment of the present application provides a transmission control method, wherein the transmission control method comprises a session management function in a process of reassigning a first user plane function network element to a second user plane function network element. The network element sends a respective session modification request of a plurality of session medication requests to each anchor user plane function network element of the plurality of anchor user plane function network elements- Each session modification request includes information about the second user plane functional network element; And the session management function network element indicates only the first anchor user plane function network element in the plurality of anchor user plane function network elements to transmit an end marker, or indicates the end marker. And transmitting only to the first anchor user plane functional network element.

In a possible design, the session management function network element sending each session modification request of the plurality of session mediation requests to each anchor user plane function network element of the plurality of anchor user plane function network elements comprises: The management function network element first sends a first session modification request from the plurality of anchor user plane function network elements to each anchor user plane function network element other than the first anchor user plane function network element, and then And sending a second session modification request to the first anchor user plane functional network element. Thus, the session management functional network element only indicates to the anchor user plane functional network element that updates the path last, to send the end marker. In this way, the end marker sent by the anchor user plane function network element that last updates the path is used to indicate that the packet transmission on the previous path is complete. Therefore, using the above-described method, it is possible to improve the user experience by avoiding data packet loss in the previous path.

In a possible design, the session management function network element directs only the first anchor user plane function network element in the plurality of anchor user plane function network elements to send an end marker, or the end marker to the first anchor user The step of transmitting only the flat function network element may include the session management function network element sending each session modification request to each anchor user other than the first anchor user plane function network element in the plurality of anchor user plane function network elements. After sending to the flat function network element, the session management function network element directs the first anchor user plane function network element to send an end marker, or an end marker to the first anchor user plane function And a step of transmitting to the network element. For example, the session management function network element instructs the first anchor user plane function network element to transmit the end marker, using a session modification request sent to the first anchor user plane function network element, Or the session modification request includes the end marker; Or the session management function network element instructs the first anchor user plane function network element to transmit the end marker using the first message sent to the first anchor user plane function network element, or the first One message contains the end marker.

In a possible design, the transmission control method further comprises the session management function network element determining the first anchor user plane function network element. For example, the first anchor user plane functional network element includes a remote user plane functional network element or a home user plane functional network element. Specifically, the session management function network element may determine a remote user plane function network element or a home user plane function network element as an anchor user plane function network element that last updates the path to achieve the above-described effect.

According to a second aspect, an embodiment of the present application provides a transmission control method, wherein the transmission control method comprises: a first user plane function network element transmitting and receiving data packets on a plurality of paths; And after the first user plane functional network element receives a first end marker on a first path, the first user plane functional network element sends the first end marker to an access network device. The first path is a path for finally transmitting end markers in the plurality of paths.

According to the above-described method, the first user plane functional network element sends the end marker to the access network device after receiving the last transmitted end marker. In this way, the end marker sent by the anchor user plane functional network element that last updates the path is used to indicate that packet transmission on the previous path is complete. Therefore, using the above-described method, it is possible to improve the user experience by avoiding data packet loss in the previous path.

In a possible design, the transmission control method further comprises: the first user plane functional network element receiving a second end marker on a second path in the plurality of paths, and discarding the second end marker. do. The second path is an arbitrary path in which the end markers were not last transmitted in the plurality of paths. In this way, storage resources of the first user plane functional network element can be saved.

In a possible design, the transmission control method comprises: the first user plane function network element receiving first indication information from a session management function network element, wherein the first indication information is sent to the first user plane function network element. And instructing to transmit the first end marker to the access network device after receiving the first end marker on the first path. For example, in the process of inserting the first user plane functional network element or in the process of reallocating the first user plane functional network element, the first user plane functional network element is the first from the session management functional network element. Instruction information is received.

In a possible design, the first indication information includes quantity information, and the quantity information indicates the quantity of a route for transmitting the end marker in the plurality of routes.

In a possible design, the transmission control method further comprises the step of determining, by the first user plane functional network element, the first path based on the first indication information. For example, when receiving an end marker in an amount equal to the number of paths for transmitting an end marker in a plurality of paths, the first user plane functional network element first path transmits an end marker for the end marker. To decide.

In a possible design, data packets transmitted and received on the plurality of paths are data packets of the first session. The transmission control method includes: the first user plane function network element receiving second indication information from the session management function network element; Detecting, by the first user plane function network element, a downlink data packet of the first session based on the second indication information; And determining, by the first user plane functional network element, the downlink data packet as the end marker based on a detection result. For example, in the process of inserting the first user plane functional network element or in the process of reassigning the first user plane functional network element, the first user plane functional network element is generated from the session management functional network element. 2 Receive instruction information.

According to a third aspect, an embodiment of the present application provides a transmission control method, wherein the transmission control method comprises: a session management function network element, a first user plane function network element, a data packet of a first session on a plurality of paths Determining to transmit and receive; And the session management function network element transmitting first indication information to the first user plane function network element. The first indication information is used for determination of a first path and to the first user plane functional network element, to receive the first end marker on the first path and then transmit the first end marker to an access network device. Instruct. The first path is a path for finally transmitting the end marker in the plurality of paths.

According to the above-described method, the session management function network element transmits the first indication information to the first user plane function network element. The first user plane functional network element transmits the end marker to the access network device based on the first indication information after receiving the last transmitted end marker. In this way, the end marker sent by the anchor user plane functional network element that last updates the route is used to indicate that the packet transmission on the previous route is complete. Therefore, using the above-described method, it is possible to improve the user experience by avoiding data packet loss in the previous path.

In a possible design, the first indication information includes quantity information, and the quantity information indicates the quantity of a route for transmitting the end marker in the plurality of routes.

In a possible design, the step of transmitting, by the session management function network element, the first indication information to the first user plane function network element may include the process of inserting the first user plane function network element or the first user plane function. In the process of reallocating network elements, the session management functional network element includes transmitting the first indication information to the first user plane functional network element.

In a possible design, the transmission control method includes the step of transmitting, by the session management function network element, second indication information to the first user plane function network element, wherein the second indication information is the first user plane function network element. It is used in the detection of the downlink data packet of the first session in-. For example, in the process of inserting the first user plane functional network element or the process of reallocating the first user plane functional network element, the session management functional network element sends the second indication information to the first user plane. Send to the functional network element.

In a possible design, the transmission control method comprises: the session management function network element determining that a third path is not switched in a plurality of paths of the first session; And sending, by the session management function network element, an end marker or third indication information to an anchor user plane function network element corresponding to the third path, wherein the third indication information transmits an end marker on the third path. In order to do so, the anchor user plane function network element is further included. In other words, the end marker needs to be transmitted regardless of whether the path is switched.

According to the fourth aspect, an embodiment of the present application provides a transmission control device. The transmission control device may be a session management function network element or a chip. The transmission control device has the function of implementing the behavior of the session management function network element in various possible designs of the first aspect, the third aspect, or the first aspect and the third aspect. The function may be implemented in hardware or may be implemented in hardware by executing corresponding software. The hardware or software includes one or more modules corresponding to the function. In a possible design, the structure of the device includes a processor and a transceiver, and the processor is configured to perform corresponding functions in various possible designs of the first side, the third side or the first side and the third side. The transceiver is configured to implement communication between the transmission control device and a first user plane functional network element or each anchor user plane functional network element. The transmission control device may further include a memory. The memory is coupled to the processor and is configured to store program instructions and data required by the transmission control device.

According to the fifth aspect, an embodiment of the present application provides a transmission control device. The transmission control device may be a user plane function network element or a chip. The transmission control device has the function of implementing the operation of the first user plane functional network element in the second aspect or in various possible designs of the second aspect. The function may be implemented in hardware or may be implemented in hardware by executing corresponding software. The hardware or software includes one or more modules corresponding to functions. In a possible design, the structure of the transmission control device includes a processor and a transceiver, and the processor is configured to perform corresponding functions in the second aspect or in various possible designs of the second aspect. The transceiver is configured to implement communication between the transmission control device and the session management function network element, each anchor user plane function network element or access network device. The transmission control device may further include a memory. The memory is coupled to the processor and is configured to store program instructions and data required by the transmission control device.

According to a sixth aspect, an embodiment of the present application provides a transmission control system, wherein the transmission control system is configured with a session management function network element and data packets configured to perform a method in various possible designs of the first aspect or the first aspect Each anchor user plane function network element that is configured to send a. Alternatively, the transmission control system may include a first user plane functional network element configured to perform methods in various possible designs of the second or second aspect, and a session configured to perform methods in the third aspect or various possible designs. Management function network element.

According to a seventh aspect, embodiments of the present application further provide a computer readable storage medium, wherein the computer readable storage medium stores instructions. When the instructions are executed on a computer, the computer can perform the method in the aspect described above.

According to an eighth aspect, an embodiment of the present application provides a computer program product including instructions. When the instructions are executed on a computer, the computer can perform the method in the aspect described above.

The above solution can solve the packet loss problem of downlink data packets in a scenario of reallocating user plane functional network elements, thereby improving the user experience.

BRIEF DESCRIPTION OF DRAWINGS To describe the technical solutions in the embodiments or background of the present invention more clearly, the following briefly describes the accompanying drawings required for describing the embodiments or background of the present invention.
1A is a schematic diagram of reassignment of a user plane functional network element.
1B is a schematic diagram of the reallocation of user plane functional network elements in a single session and multi-session anchor scenario.
2A is a schematic diagram of a 5G communication system.
2B is another schematic diagram of a 5G communication system in a service framework.
3A is a schematic diagram of an uplink classifier (ULCL).
3B is a schematic diagram of an Internet Protocol version 6 (IPv6 multi-homing) session.
4A and 4B are signaling interaction diagrams of a transmission control method according to an embodiment of the present application.
5 is a flowchart of a transmission control method according to an embodiment of the present application.
6A and 6B are signaling interaction diagrams of a transmission control method according to another embodiment of the present application.
7A is a flowchart of a transmission control method according to another embodiment of the present application.
7B is another flowchart of a transmission control method according to another embodiment of the present application.
8 is a schematic structural diagram of a transmission control device according to an embodiment of the present application.
9 is a schematic structural diagram of a transmission control device according to an embodiment of the present application. and
10 is a schematic structural diagram of a transmission control device according to an embodiment of the present application.

The following clearly describes the technical solutions in the embodiments of the present application with reference to the accompanying drawings in the embodiments of the present application.

In the 5G mobile network architecture, the core network includes a control plane network element and a user plane network element. The control plane network element includes the existing third generation partnership project (3GPP) control network element mobility management entity (MME), the control plane function of the serving gateway (SGW) and the packet data network gateway. (packet data network gateway, PGW) is an integrated control plane. The user plane function network element may implement user plane functions (SGW-U and PGW-U) of the SGW and PGW. Further, the unified control plane network element may be decomposed into an access and mobility management function (AMF) network element and a session management function (SMF) network element.

2A is a schematic diagram of a 5G communication system according to an embodiment of the present application. As shown in FIG. 2A, the communication system includes at least a UE 201, an access network (AN) device 202, an AMF network element 203, an SMF network element 204, and a user plane function. function, UPF) network element 205.

The UE 201 included in this system is not limited to 5G networks, and includes mobile phones, Internet of Things devices, smart home devices, industrial control devices, and vehicle devices. User equipment may also be a terminal, terminal device, mobile station, mobile console, remote station, remote terminal, access terminal, user It may be referred to as a user terminal (User Terminal) or a user agent (User Agent), and is not limited thereto. The user equipment may also be a vehicle in vehicle-to-vehicle (V2V) communication, a machine in machine type communication, or the like.

AN device 202 is a device configured to provide wireless communication function to UE 201. The AN device 202 may be a radio access network (RAN) device. The (R) AN device may include various base stations such as macro base stations, micro base stations (also referred to as small cells), relay stations or access points. In systems that use different radio access technologies, the names of devices with the functionality of a base station can be different. For example, in the 3G (3 ^rd generation, 3G) system, the device has a function of a base station is referred to as a Node B (NodeB); In a Long Term Evolution (LTE) system, a device having the function of a base station is referred to as an evolved NodeB (evolved NodeB, eNodeB); Or in a 5th generation system, a device having the function of a base station is referred to as gNB (gNodeB).

The AMF network element 203 may be responsible for registration of the UE 201, mobility management, and tracking area update procedure.

The SMF network element 204 may be responsible for session management of the UE 201. For example, session management includes establishing, modifying or releasing sessions, selecting or reselecting UPF network elements, and assigning an Internet protocol (IP) address.

The UPF network element 205 may be connected to a data network (DN) 206 and may be configured to implement transmission of service data packets.

The aforementioned network elements may also be referred to as devices or entities. For example, an AMF network element may also be referred to as an AMF device or AMF entity.

The above-described network elements may be implemented by specific hardware, may be implemented by software instances on specific hardware, or by virtualized functions instantiated on a suitable platform. This is not limited in the present invention.

For example, FIG. 2B is another schematic diagram of a 5G communication system in a service framework. Similarly, the communication system includes at least UE 201 ', AN device 202', AMF network element 203 ', SMF network element 204' and UPF network element 205 '. The functions of the UE 201 ', the AN device 202', the AMF network element 203 ', the SMF network element 204', and the UPF network element 205 'in FIG. The functions of the AN device 202, AMF network element 203, SMF network element 204, and UPF network element 205 are the same. Details are not described again here.

In the service framework, a service-based interface is used on the control plane. For example, AMF network element 203 'and SMF network element 204' have service-based interfaces Namf and Nsmf, respectively. A functional network element may open its capabilities to other authenticated functional network elements using a service-based interface to provide a network function (NF) service. That is, NF services are various capabilities that can be provided.

In addition, this embodiment of the present application may be further applied to other future-oriented communication technologies. The network architecture and service scenario described in this application are intended to more clearly describe the technical solution of the present application, but are not intended to limit the technical solution provided in the present application. Those skilled in the art will appreciate that as the network architecture evolves and new service scenarios emerge, the technical solutions provided in this application also apply to similar technical problems.

This application is intended to provide a transmission control solution in single session and multi session anchor scenarios. For example, to support offloading of a local service flow, the SMF controls the data path of a single PDU session, so that the PDU session can simultaneously correspond to multiple N6 interfaces. The N6 interface is the interface between UPF and DN. The UPF terminating the N6 interface may be referred to as an anchor UPF. Thus, each anchor UPF provides a different access path connected to the same DN. In other words, one PDU session has multiple paths (which may also be referred to as multiple branches) corresponding to different anchor UPFs.

For example, single session and multi-session anchor scenarios include ULCL scenarios or IPv6 multi-homing session scenarios.

3A is a schematic diagram of a ULCL scenario. For example, in the case of an Internet Protocol version 4 (IPv4), IPv6 or Ethernet type PDU session, the SMF may decide to insert the ULCL UPF in the data path of the PDU session. ULCL UPF offloads the uplink service flow to different anchor UPFs on different branches (e.g., anchor UPF 1 and anchor UPF 2 in FIG. 3A), or combines downlink service flows from different branches and then combines them. The downlink service flow is transmitted to the UE. The anchor UPF 1 is a local user plane function network element (local UPF), and the anchor UPF 2 is a remote user plane function network element (remote UPF). The UE is unaware of ULCL's offloading. For a PDU session of type IPv4 or IPv6, the UE associates a single IPv4 address or single IPv6 prefix with the PDU session.

In addition, there may be a plurality of ULCL UPFs in the data path of the PDU session. One UPF can also have the functions of both ULCL UPF and anchor UPF.

3B is a schematic diagram of an IPv6 multiple homing session scenario. In the case of an IPv6 multiple homing session, one PDU session may be associated with multiple IPv6 prefixes. Likewise, different anchor UPFs (e.g., anchor UPF 1 and anchor UPF 2 in the figure) provide different access paths (i.e., branches) connected to the same DN. After converging to a UPF supporting a branch point (BP) function, a downlink service flow from different branches is transmitted to the UE. UPF may be referred to as BP UPF. The BP UPF can further forward the uplink service flow to different anchor UPFs on different branches. For example, anchor UPF 1 is a local user plane functional network element and anchor UPF 2 is a remote user plane functional network element. One UPF can have both BP UPF and anchor UPF functions.

Specifically, in single-session and multi-session anchor scenarios, the I-UPF is in the data path of the PDU session. The UPF may be the ULCL UPF in FIG. 3A or the BP UPF in FIG. 3B.

When the UE 201 moves, a RAN handover is triggered, and the RAN handover may cause re-allocation of the I-UPF. I-UPF reassignment may also be referred to as redirection. When the I-UPF is reassigned, it is shown in Figure 1B. Before the UE moves, the established PDU session can be offloaded using the source I-UPF. For example, the source I-UPF has two session branches, branch 1 corresponds to the anchor UPF 1, and branch 2 corresponds to the anchor UPF 2. When I-UPF reassignment occurs, there may be two cases. Case 1: Both branches are switched towards the target. Case 2: Only the primary branch (eg, branch 1) is switched towards the target, and the secondary branch (eg, branch 2) is not switched.

In one of the cases described above, when any branch in the PDU session (e.g., branch 1) is switched, after all data packets on the switched branch are transmitted, the anchor UPF corresponding to the switched branch is the end marker Is transmitted to the target RAN through the source RAN. After receiving the end marker, the target RAN assumes that the transmission of the downlink data packet through the previous path ends, and starts to transmit the downlink data packet received through the new path to the UE. However, transmission of a downlink data packet through another branch (eg, branch 2) in a PDU session may not be completed. Since these data packets are received after the end markers are received, the target RAN discards these data packets directly. This results in data packet loss, reducing the user experience.

In order to solve the above technical problem, the present application provides a plurality of solutions.

4A, 4B, and 5 are signaling interaction diagrams and flowcharts of a first transmission control method according to an embodiment of the present application. Under control in the first solution, only the first anchor user plane functional network element in the plurality of anchor user plane functional network elements transmits the end marker.

4A and 4B show the interaction between UE, source RAN, target RAN, AMF, SMF, source I-UPF, target I-UPF, anchor UPF 1 and anchor UPF 2. For example, the UE may be the UE 201 of FIG. 2A or the UE 201 'of FIG. 2B. The source RAN or target RAN may be the AN device 202 of FIG. 2A or the AN device 202 'of FIG. 2B. The AMF may be the AMF network element 203 of FIG. 2A or the AMF network element 203 'of FIG. 2B. The SMF may be the SMF network element 204 of FIG. 2A or the SMF network element 204 'of FIG. 2B. The source I-UPF, target I-UPF, anchor UPF 1 or anchor UPF 2 may be the UPF network element 205 of FIG. 2A or the UPF network element 205 'of FIG. 2B. In the ULCL scenario, the I-UPF is the ULCL UPF. In the IPv6 multi-homing session scenario, the I-UPF is the BP UPF.

In the example of FIGS. 4A and 4B, the PDU session has two branches corresponding to anchor UPF 1 and anchor UPF 2, respectively. However, the present application is not limited to this, and the PDU session may further have a plurality of branches (or paths) of different quantities.

4A and 4B, the method includes the following steps.

Before the UE moves, the PDU session between the UE and the DN can be established using a session establishment procedure. The PDU session has a branch 1 corresponding to the anchor UPF 1 and a branch 2 corresponding to the anchor UPF 2. In this case, a path of an uplink (UL) / downlink (DL) data packet includes one path through the UE, source RAN, source I-UPF and anchor UPF 1; And other paths through the UE, source RAN, source I-UPF and anchor UPF 2.

The UE's movement triggers RAN handover. For example, the RAN handover may be an Xn-based handover. The RAN handover includes at least a handover preparation phase and a handover execution phase. After the handover preparation step, the target RAN may serve the UE. For example, the path of the uplink data packet includes one path through the UE, the target RAN, the source I-UPF and the anchor UPF 1; And other paths through the UE, target RAN, source I-UPF and anchor UPF 2. The downlink data packet is transmitted to the UE through a forwarding tunnel between the source RAN and the target RAN.

Step 401. The target RAN sends a path switch request to the AMF.

For example, after the handover execution step, the target RAN sends a path switch request to the AMF to inform the AMF that the UE has moved to a new target cell. The path switch request may be an N2 path switch request. The path switch request carries PDU session and session management (SM) information to be switched. For example, SM information is N2 SM information, and N2 SM information includes information about a target RAN. The information on the target RAN may include the address and tunnel information of the target RAN. For example, the tunnel information of the target RAN includes an uplink tunnel identifier and a downlink tunnel identifier of the target RAN.

Step 402. The AMF sends a context update request to the SMF.

For example, the AMF can send a request to the SMF and invoke the SMF's service: Nsmf_PDU Session_Update SM Context. The request to call the service carries the PDU session to be switched, SM information, and location information of the UE.

After receiving the request, the SMF determines whether the current UPF (ie, source I-UPF) can continue serving the UE. If the source I-UPF cannot continue serving the UE, the SMF selects the target I-UPF based on the location information of the UE.

Step 403a. The SMF sends a session establishment request to the target I-UPF.

The session establishment request is used to request N4 session establishment between the SMF and the target I-UPF. For example, the session establishment request is an N4 session establishment request. The session establishment request includes information about the target RAN.

Step 403b. The target I-UPF sends a session establishment response to the SMF.

After receiving the session establishment request, the target I-UPF feeds back the session establishment response to the SMF. For example, the session establishment response is an N4 session establishment response. The session establishment response includes information about the target I-UPF. The information about the target I-UPF may include at least one of an address of the target I-UPF and tunnel information of the target I-UPF. For example, the tunnel information of the target I-UPF includes at least the tunnel identifier of the downlink user plane of the target I-UPF.

Step 404a. The SMF sends a session modification request to the anchor UPF 1.

Step 404b. The anchor UPF 1 sends a session modification response to the SMF.

Step 405a. The SMF sends a session modification request to the anchor UPF 2.

Step 405b. The anchor UPF 2 sends a session modification response to the SMF.

Steps 404a-405b are used to update the user plane information of the anchor UPF on each branch. For example, the session modification request in steps 404a and 405a may be an N4 session modification request, and includes information about the target I-UPF. Updating the user plane information of the anchor UPF refers to updating information about the source I-UPF stored in the anchor UPF with information about the target I-UPF. After the update of the user plane information is completed, the path switch (or referred to as path update) may be considered complete. The session modification response in steps 404b and 405b may be an N4 session modification response.

If the SMF decides to switch only some branches in the PDU session, only the user plane information of the anchor UPF on the branch to be switched can be updated. In this case, in the case of a branch that has not been switched, since a session modification request is not transmitted, user plane information may not be updated. Alternatively, the SMF may use a session modification request to indicate to the anchor user plane functional network element on the unswitched branch to stop transmission of the downlink data packet.

In a first transmission control solution, the SMF only instructs one anchor user plane (which may be referred to as a first anchor user plane functional network element) in a plurality of anchor user plane functional network elements to transmit end markers.

Optionally, after the SMF updates the user plane information of at least one anchor user plane function network element in a plurality of anchor user plane function network elements other than the first anchor user plane function network element, the SMF is configured to send an end marker. Indicate to the first anchor user plane functional network element.

In the example of FIGS. 4A and 4B, it is assumed that both branch 1 and branch 2 are switched. The SMF first updates the user plane information of the anchor UPF 1 using steps 404a and 404b. The SMF then updates the user plane information of the anchor UPF 2 using steps 405a and 405b. After step 404b, the SMF can instruct anchor UPF 2 to send the end marker on branch 2.

In a first possible implementation, the SMF can direct the anchor UPF 2 to send an end marker on branch 2 using the session modification request of step 405a. Specifically, the request for session modification in step 405a includes (1) a function of requesting an update of user plane information of anchor UPF 2; And (2) instruct anchor UPF 2 to transmit the end marker on branch 2. For example, the request to modify the session in step 405a carries indication information used to direct the anchor UPF 2 to send the end marker.

In a second possible implementation, the SMF can direct the anchor UPF 2 to send an end marker on branch 2 using another message (eg, the first message), as shown in step 405c. In other words, after updating the user plane information of the anchor UPF 2 in steps 405a and 405b, the SMF can use the first message to instruct the anchor UPF 2 to send the end marker on the branch 2. For example, the first message carries indication information used to indicate to the anchor UPF 2 to send the end marker. The first message may also be a session modification request. However, the difference from the first implementation is that the session modification request used to request to update the user plane information of the anchor UPF 2 and the session modification request used to instruct the anchor UPF 2 to send the end marker on branch 2 are 2 It can be implemented by two different messages.

In the two implementations described above, in a plurality of anchor user plane functional network elements, only the anchor user plane functional network element that last updates the user plane information transmits the end marker. Optionally, prior to step 404a, the SMF first selects which anchor user plane function network element is the anchor user plane function network element that last updates the user plane information, i.e., which anchor user plane function network element. Can select whether is the first anchor user plane functional network element transmitting the end marker. For example, the SMF may be configured for a remote user plane functional network element in a ULCL or IPv6 multi homing session scenario, a home user plane functional network element in a roaming scenario, or a UE (or target RAN) in various anchor user plane functional network elements. Another anchor user plane functional network element having the longest path may be determined as the first anchor user plane functional network element. Optionally, the SMF first updates the user plane information of the anchor user plane functional network element with a relatively short path, based on the length of the path between the anchor user plane functional network element and the UE (or target RAN), and then Update user plane information of the anchor user plane function network element with a relatively long path. In this way, the anchor user plane function network element that last updates the user plane information is the anchor user plane function network element having the longest path to the UE (or target RAN), that is, the first anchor user plane function network element. .

Alternatively, in a second possible implementation, after the SMF updates the user plane information for each anchor user plane function network element of the path to be switched, the SMF lastly updates the user plane information with the anchor user plane function. The network element is determined as the first anchor user plane functional network element. Similarly, the SMF may first update the user plane information of the anchor user plane functional network element with a relatively short path, based on the length of the path between the anchor user plane functional network element and the UE (or target RAN), The user plane information of the anchor user plane function network element with a relatively long path is then updated. In this way, the anchor user plane function network element that last updates the user plane information is the anchor user plane function network element having the longest path to the UE (or target RAN), that is, the first anchor user plane function network element. . For example, the first anchor user plane functional network element includes a remote user plane functional network element in a ULCL or IPv6 multiple homing session scenario or a home user plane functional network element in a roaming scenario.

For example, in the example of FIGS. 4A and 4B, in ULCL or IPv6 multi-homing session scenario, anchor UPF 1 is a local user plane functional network element used for local offloading, and anchor UPF 2 is a remote user plane functional network element. Is (shown in Figure 3a or Figure 3b). Therefore, the SMF only instructs the anchor UPF 2 to transmit the end marker.

In addition, in addition to configuring the end marker by the anchor UPF after the anchor UPF receives the indication information of the SMF, the end marker may be configured by the SMF differently. Therefore, the SMF can only send the end marker to the first anchor user plane function network element in a plurality of anchor user plane function network elements, so the first anchor user plane function network element is located at the first anchor user plane function network element. End markers can be sent on the route. Details are not described again here.

Step 406. Anchor UPF 2 sends the end marker to the source I-UPF.

For example, after receiving the indication or end marker sent by the SMF using step 405a or 405c, anchor UPF 2 sends the end marker after path switching. However, the anchor UPF 1 does not transmit the end marker because the anchor UPF 1 does not receive the indication information regarding transmitting the end marker and does not receive the end marker.

Step 407. After receiving the end marker, the source I-UPF sends the end marker through the source RAN to the target RAN.

After receiving the end marker, it may be considered that the target RAN ends transmission of the downlink data packet through the previous path and starts to transmit the downlink data packet received on the new path to the UE. For example, a new path of a downlink data packet includes an anchor UPF 1, a target I-UPF, a target RAN and one path through the UE; And anchor UPF 2, target I-UPF, target RAN and other paths through the UE.

Step 408. The SMF sends a context update response to the AMF.

For example, the context update response may be a response message of the called service "Nsmf_PDU Session_Update SM Context". The context update response carries the address of the target I-UPF and the uplink tunnel information of the target I-UPF.

Step 409. The SMF sends a path switch acknowledgment (acknowledgment) to the target RAN.

For example, the path switch acknowledgment may be an N2 path switch request acknowledgment. The path switch acknowledgment carries the address of the target I-UPF and the uplink tunnel information of the target I-UPF.

After receiving the path switch acknowledgment, the target RAN can transmit an uplink data packet on the new path. For example, the new path of the uplink data packet passes through the UE, target RAN, target I-UPF and anchor UPF 1; Other new routes go through the UE, target RAN, target I-UPF and anchor UPF 2.

Step 410. The target RAN notifies the source RAN to release the resource.

For example, after confirming that the switching is successful, the target RAN sends a source release message to the source RAN to trigger the release of resources of the source RAN.

4A and 4B, as shown in FIG. 5, an embodiment of the present application provides a transmission control method including the following steps.

Step 501. In the process of reassigning the first user plane function network element to the second user plane function network element, the session management function network element may request a plurality of anchor user plane functions for each session modification request of a plurality of session medication requests. Each anchor user plane functional network element in the network element is transmitted, and each session modification request of a plurality of session mediation requests includes information about the second user plane functional network element.

For example, the first user plane functional network element may be the source I-UPF in FIGS. 4A and 4B, and the second user plane functional network element may be the target I-UPF in FIGS. 4A and 4B, The session management function network element may be SMF in FIGS. 4A and 4B. The plurality of anchor user plane functional network elements may include anchor UPF 1 and anchor UPF 2 in FIGS. 4A and 4B.

For step 501, reference is made to the description of steps 404a and 405a in FIGS. 4A and 4B, and details of the new terms are not described herein again.

Step 502. The session management function network element indicates only the first anchor user plane function network element in the plurality of anchor user plane function network elements to send the end marker; Alternatively, the session management function network element sends an end marker only to the first anchor user plane function network element.

For example, the first anchor user plane functional network element may be anchor UPF 2 in FIGS. 4A and 4B.

For example, the session management functional network element directs the first anchor user plane functional network element to send an end marker using the session modification request sent to the first anchor user plane functional network element, or the session modification request is End markers; or

The session management function network element directs the first anchor user plane function network element to send the end marker using the first message sent to the first anchor user plane function network element, or the first message includes the end marker do.

For step 502, reference is made to the description of steps 405a or 405c in FIGS. 4A and 4B, and details are not described herein again.

For example, in step 501, the session management function network element first makes each first session modification request, each anchor user plane function network in a plurality of anchor user plane function network elements other than the first anchor user plane function network element. Sending to the element, and then sending a second session modification request to the first anchor user plane functional network element. In other words, the first anchor user plane function network element is an anchor user plane function network element that, in a plurality of anchor user plane function network elements, finally receives a session modification request and updates the path. Therefore, the session management function network element only indicates the anchor user plane function network element that last updates the path to send the end marker. In this way, each anchor user plane function network element of a plurality of anchor user plane function network elements, except for the first anchor user plane function network element, when the anchor user plane function network element last updating the path sends an end marker. Completed the path switch, that is, the transmission of the downlink data packet on the corresponding branch was completed. Thus, the end marker sent by the anchor user plane functional network element that last updates the path is used to indicate that packet transmission on the previous path is complete. Thus, using the above method, it is possible to improve the user experience by avoiding data packet loss on the previous path.

Optionally, after the session management function network element sends each session modification request to each anchor user plane function network element in a plurality of anchor user plane function network elements excluding the first anchor user plane function network element, step ( 502) may be performed. For example, a plurality of anchor user plane function network elements include anchor user plane function network elements A, B, and C, and the first anchor user plane function network element is an anchor user plane function network element C, and each modification request Is sent to each of the anchor user plane function network elements A and B, then the session management function network element directs the anchor user plane function network element C to send the end marker, or the end marker to the anchor user plane function network element C. I can send it. As described above, a session modification request or other message sent to the anchor user plane function network element C directs the anchor user plane function network element C to send an end marker, or an end marker to the anchor user plane function network element C. Can be used to transmit. Details are not described again here. Network resource when a session modification request sent to the anchor user plane function network element C is used to instruct the anchor user plane function network element C to send an end marker or to send an end marker to the anchor user plane function network element C. The signaling interaction can be further reduced to save the time.

Optionally, the method further comprises the session management functional network element determining a first anchor user plane functional network element. For example, the session management functional network element may designate a specific anchor user plane functional network element as a first anchor user plane functional network element that sends an end marker. For example, the session management functional network element may determine the first anchor user plane functional network element before sending each session modification request to each of the plurality of anchor user plane functional network elements, or multiple requests for each session modification. The first anchor user plane functional network element may be determined after transmission to each of the anchor user plane functional network elements.

For example, a specific anchor user plane function network element may be a remote user plane function network element, a home user plane function network element, or an anchor user having the longest path to a UE (or target RAN) in various anchor user plane function network elements. It may include a planar functional network element. If the particular anchor user plane functional network element is an anchor user plane functional network element that updates the path last, the above-described effect can be achieved. If the first anchor user plane function network element is not the anchor user plane function network element that last updates the path, the data on the other previous paths if the first anchor user plane function network element sends an end marker after updating the path. Packet transmission is basically completed. Thus, data packet loss in the previous path can be reduced, and the user experience is improved.

6A and 6B are signaling interaction diagrams of a second transmission control method according to an embodiment of the present application. According to the second solution, after receiving the end markers transmitted by the plurality of anchor user plane functional network elements, the source I-UPF sends the end markers through the source RAN to the target RAN.

Similarly, FIGS. 6A and 6B show the interaction between UE, source RAN, target RAN, AMF, SMF, source I-UPF, target I-UPF, anchor UPF 1 and anchor UPF 2. For details, refer to the descriptions in FIGS. 4A and 4B, and details are not described again.

6A and 6B, the method includes the following steps.

Step 601. The target RAN sends a path switch request to the AMF.

Step 602. The AMF sends a context update request to the SMF.

Step 603a. The SMF sends a session establishment request to the target I-UPF.

Step 603b. The target I-UPF sends a session establishment response to the SMF.

Step 604a. The SMF sends a session modification request to the anchor UPF 1.

Step 604b. The anchor UPF 1 sends a session modification response to the SMF.

Step 605a. The SMF sends a session modification request to the anchor UPF 2.

Step 605b. The anchor UPF 2 sends a session modification response to the SMF.

For steps 601 to 605b and related operations prior to step 601, refer to the descriptions of steps 401 to 405b in FIGS. 4A and 4B, and details are not described herein again.

Step 606. The SMF sends the first indication information to the source I-UPF. The first indication information instructs the source I-UPF to send the end marker to the access network device after receiving the end markers transmitted on each branch. Alternatively, the first indication information instructs the source I-UPF to send the last received end marker to the access network device after receiving the last end marker.

For example, the first indication information includes quantity information. The quantity information indicates the quantity of a route for transmitting an end marker in a plurality of routes. In the second solution, that is, the quantity information indicates the quantity of routes to be switched in a plurality of routes. The quantity information may be a specific value for the quantity of a route for transmitting end markers in a plurality of routes. Alternatively, the quantity information may be tunnel information of a path for transmitting end markers in a plurality of paths. In the example of FIGS. 6A and 6B, the quantity information may be 2, indicating that the end marker is transmitted in two paths; Alternatively, the quantity information may be tunnel information of branch 1 and branch 2, which indicates that the end marker is transmitted through two paths of branch 1 and branch 2.

For example, the SMF sends a session modification request to the source I-UPF, where the session modification request includes first indication information. Optionally, after receiving the session modification request, the source I-UPF returns a session modification response to the SMF.

In the example of FIGS. 6A and 6B, the SMF transmits the first indication information to the source I-UPF in the I-UPF reallocation process. It should be noted that the case of performing step 606 is not limited in this application, and the SMF can perform step 606 at any moment after step 602 in the I-UPF reassignment process. Alternatively, the SMF may transmit the first indication information to the source I-UPF before reallocation of the I-UPF. For example, in the process of inserting the source I-UPF, the SMF may transmit the first indication information to the source I-UPF. Optionally, the source I-UPF may be inserted in the session establishment procedure, or the source I-UPF may be inserted after the session establishment procedure is finished.

Step 607. The SMF sends the second indication information to the source I-UPF. The second indication information is used for detection of downlink data packets of the first session in the source I-UPF.

Similarly, in the example of FIGS. 6A and 6B, the SMF sends the second indication information to the source I-UPF in the I-UPF reassignment process. It should be noted that the case of performing step 607 is not limited in this application, and the SMF can perform step 607 at any moment after step 602 in the I-UPF reassignment process. Alternatively, the SMF can transmit the second indication information to the source I-UPF before reallocation of the I-UPF. For example, in the process of inserting the source I-UPF, the SMF may transmit the second indication information to the source I-UPF. Optionally, the source I-UPF may be inserted in the session establishment procedure, or the source I-UPF may be inserted after the session establishment procedure is finished.

The first session is a session corresponding to branch 1 and branch 2.

Step 608a. After completing the path switching, the anchor UPF 1 sends the end marker 1 to the source I-UPF.

Step 608b. After completing the path switching, the anchor UPF 2 sends the end marker 2 to the source I-UPF.

The source I-UPF detects the received downlink data packet of the first session based on the second indication information, and determines the downlink data packet as an end marker based on the detection result. For example, the source I-UPF receives each downlink data packet on branch 1 and branch 2, and each downlink data packet includes a packet header and data. Branch 1 and branch 2 are session branches of the first session. Therefore, downlink data packets transmitted on branch 1 and branch 2 are downlink data packets of the first session. The source I-UPF detects each received downlink data packet, and determines the downlink data packet of the first session as an end marker based on the packet header. Thus, the source I-UPF knows that end marker 1 and end marker 2 have been received.

Step 609. After receiving the end marker on the first path, the source I-UPF transmits the end marker through the source RAN to the target RAN based on the first indication information. The first path is a path that transmits the end marker last.

In other words, after receiving each end marker transmitted on each branch (i.e., after receiving the last transmitted end marker), the source I-UPF sends the end marker through the source RAN to the target RAN. 6A and 6B, branch 2 is a path for finally transmitting the end marker.

For example, the source I-UPF determines branch 2 as the first path based on the first indication information. When the source I-UPF receives an end marker of the same quantity as the quantity indicated by the quantity information, the source I-UPF determines the route for the last transmission of the end marker, namely, branch 2 as the first route. For example, if the first indication information is a specific value for the quantity of a path for transmitting an end marker in a plurality of paths, for example, "2", after receiving the two end markers, the source I-UPF Determines a path for finally transmitting the end marker as the first path. Alternatively, if the quantity information is tunnel information of a path for transmitting end markers in a plurality of paths, for example, tunnel information of branch 1 and branch 2, after receiving the end markers transmitted on branch 1 and branch 2, The source I-UPF determines the path for the last transmission of the end marker as the first path.

Optionally, for end markers previously received on another route, for example end marker 1 received on branch 1, the source I-UPF may discard the end marker.

After receiving the end marker, the target RAN may consider that the transmission of the downlink data packet on the previous path ends, and start to transmit the downlink data packet received on the new path to the UE. For example, a new path of a downlink data packet includes an anchor UPF 1, a target I-UPF, a target RAN and one path through the UE; And anchor UPF 2, target I-UPF, target RAN and other paths through the UE.

Step 610. The SMF sends a context update response to the AMF.

Step 611. The SMF sends a path switch acknowledgment to the target RAN.

Step 612. The target RAN notifies the source RAN to release the resource.

For steps 610 to 612, reference is made to the description of steps 408 to 410 in FIGS. 4A and 4B, and details are not described herein again.

The solutions of FIGS. 6A and 6B are applicable to scenarios where there are at least two paths to be switched in multiple paths. Before reallocating the I-UPF, if the source I-UPF transmits and receives data packets on two paths, the two paths are switched, as illustrated in Figures 6A and 6B. Before reallocating the I-UPF, if the source I-UPF transmits and receives data packets on two or more paths, there may be at least two paths to be switched in the plurality of paths, and other paths that are not switched. In the case of a non-switched path, the SMF does not instruct the anchor user plane functional network element on the unswitched path to send the end marker, and does not send the end marker to the anchor user plane functional network element on the unswitched path. In addition, as described in FIGS. 4A and 4B, in the case of a non-switched path, the SMF may not transmit a session modification request, so user plane information is not updated. Alternatively, the SMF may use a session modification request to instruct the anchor user plane functional network element on the unswitched path to stop transmitting the downlink data packet.

For example, before reallocating the I-UPF, the source I-UPF transmits and receives data packets on three paths, and the three paths are path a, path b and path c. When all three paths are switched, the first indication information may be 3, or tunnel information of path a, path b and path c, indicating that the end marker will be transmitted on the three paths. After receiving the three end markers, the source I-UPF sends the end markers to the target RAN via the source RAN. If only path a and path b are switched in three paths and path c is not switched, the first indication information may be 2 or tunnel information of paths a and b, indicating that the end marker is transmitted on the two paths. . After receiving the two end markers, the source I-UPF sends the end markers to the target RAN via the source RAN.

In addition, in the case of a scenario in which multiple paths have unswitched paths, the present application further provides a third solution. Similar to the second solution, after receiving the end markers transmitted by the plurality of anchor user plane functional network elements, the source I-UPF sends the end markers through the source RAN to the target RAN. However, for the unswitched path, the session management functional network element still instructs the anchor user plane functional network element on the unswitched path to send the end marker, or sends the end marker to the anchor user plane functional network element. Accordingly, after receiving the indication information or the end marker, the anchor user plane functional network element on the unswitched path sends the end marker to the source I-UPF. In other words, the end marker must be transmitted on the path regardless of whether the path is switched.

In a third solution, after receiving the end markers transmitted by the plurality of anchor user plane functional network elements, the source I-UPF targets the end markers through the source RAN, based on the first indication information sent by the SMF. Can transmit to RAN. 6A and 6B for a related description of the first indication information. Details are not described again here. Alternatively, the source I-UPF can be configured to receive the end marker sent by the plurality of anchor user plane functional network elements and then send the end marker through the source RAN to the target RAN.

Further, the first indication information (quantity information) can be used to indicate the quantity of the path for transmitting the end markers in a plurality of paths, and in the third solution, the end markers are used for each path regardless of whether the paths are switched The first indication information (quantity information) can be used to indicate the quantity of a plurality of paths.

Similar to the second solution, the source I-UPF receives the second indication information from the SMF, detects the downlink data packet of the first session based on the second indication information, and knows that the downlink data packet is an end marker. Can be. 6A and 6B for a description of the second instruction information. Details are not described again here.

Referring to the second solution and the third solution, as illustrated in FIG. 7A, an embodiment of the present application provides a transmission control method including the following steps.

Step 701. The first user plane functional network element transmits and receives data packets on a plurality of paths.

For example, the first user plane functional network element may be the source I-UPF in FIGS. 6A and 6B. The plurality of paths may be branch 1 and branch 2 in FIGS. 6A and 6B.

Step 702. After receiving the first end marker on the first path, the first user plane functional network element sends the first end marker to the access network device, where the first path is for finally transmitting the end marker in the plurality of paths. It is a path.

For example, the first path may be branch 2 in FIGS. 6A and 6B, and the first end marker is end marker 2 transmitted on branch 2. The access network device may be the source RAN in FIGS. 6A and 6B. Since the first end marker is forwarded by the source RAN and finally transmitted to the target RAN, the access network device can also be understood as the target RAN in FIGS. 6A and 6B.

For step 702, reference is made to the description of step 609 in Figures 6A and 6B, and details are not described herein again.

According to the transmission control solution, the first user plane functional network element sends the end marker to the access network device after receiving the last transmitted end marker. In this way, when the anchor user plane function network element that last updates the path sends an end marker, the other anchor user plane function network element has completed path switching, i.e., completes the transmission of downlink data packets on the branch. did. Thus, the end marker sent by the anchor user plane functional network element that last updates the path is used to indicate that packet transmission on the previous path is complete. Therefore, using the above-described method, it is possible to improve the user experience by avoiding data packet loss in the previous path.

For the last non-transmitted end marker, for example end marker 1 transmitted on branch 1, the first user plane functional network element accesses the last untransmitted end marker together with the last transmitted end marker. Can be sent to. Alternatively, the first user plane functional network element may directly discard the last marker that was not transmitted. Specifically, optionally, the method further includes the first user plane functional network element receiving a second end marker on the second path in the plurality of paths and discarding the second end marker. The second path is any path that has not last transmitted the end marker in a plurality of paths. In this way, storage resources of the first user plane functional network element can be stored. For example, the second path may be branch 1 in FIGS. 6A and 6B, and the second end marker is end marker 1 transmitted on branch 1.

Optionally, the method further comprises the first user plane function network element receiving first indication information from the session management function network element, wherein the first indication information is sent to the first user plane function network element. After receiving the first user information on the 1 path, it is instructed to transmit the first end marker to the access network device. For example, the session management function network element may be SMF in FIGS. 6A and 6B.

For this step, refer to the description of step 606 of FIGS. 6A and 6B. For example, in the process of inserting the first user plane functional network element or the process of reallocating the first user plane functional network element, the first user plane functional network element receives the first indication information from the session management functional network element can do. The first indication information includes the quantity information, and the quantity information indicates the quantity of the route for transmitting the end marker in a plurality of routes. Accordingly, the first user plane functional network element may determine the first route based on the first indication information. For example, when receiving end markers in the same quantity as the number of paths for transmitting the end markers in a plurality of paths, the first user plane function network element uses the path for the last transmission of the end markers as the first path. Decide.

Optionally, data packets transmitted and received on a plurality of paths are data packets of the first session. The method includes the steps of: receiving, by a first user plane functional network element, second indication information from a session management functional network element; Detecting a downlink data packet of the first session based on the second indication information; And determining a downlink data packet as an end marker based on the detection result.

For this step, refer to the description of step 607 in FIGS. 6A and 6B. For example, in the process of inserting the first user plane functional network element or the process of reallocating the first user plane functional network element, the first user plane functional network element receives the second indication information from the session management functional network element. can do.

7B illustrates a transmission control method according to an embodiment of the present application, and the method includes the following steps.

Step 711. The session management functional network element determines that the first user plane functional network element transmits and receives data packets of the first session on multiple paths.

Step 712. The session management function network element sends the first indication information to the first user plane function network element. The first indication information is used for the determination of the first path, and instructs the first user plane functional network element to transmit the first end marker to the access network device after receiving the first end marker on the first path. . The first path is a path for finally transmitting end markers in a plurality of paths.

For step 712, reference is made to the description of step 606 of FIGS. 6A and 6B, and details are not described herein again.

According to the aforementioned method, the session management function network element transmits the first indication information to the first user plane function network element. The first user plane functional network element transmits the end marker to the access network device based on the first indication information after receiving the last transmitted end marker. In this way, the end marker sent by the anchor user plane functional network element that last updates the path indicates that the packet transmission on the previous path is complete. Therefore, using the above-described method, it is possible to improve the user experience by avoiding data packet loss in the existing path.

Optionally, the first indication information includes the quantity information, and the quantity information indicates the quantity of the route for transmitting the end marker in a plurality of routes.

Optionally, the session management function network element sending the first indication information to the first user plane function network element is in the process of inserting the first user plane function network element or the process of reallocating the first user plane function network element. , The session management function network element transmitting the first indication information to the first user plane function network element.

Optionally, the method further comprises the step of the session management function network element transmitting the second indication information to the first user plane function network element, wherein the second indication information is provided in the first user plane function network element. It is used to detect downlink data packets of one session. For example, in the process of inserting the first user plane function network element or in the process of reallocating the first user plane function network element, the session management function network element sends second indication information to the first user plane function network element. do.

Optionally, for the third solution described above, the method further comprises: the session management function network element determining that the third path is not switched in a plurality of paths of the first session; And transmitting, by the session management function network element, the end marker or the third indication information to the anchor user plane function network element corresponding to the third route, where the third indication information indicates the end marker on the third route. Instruct the anchor user plane functional network element to transmit. In other words, the end marker must be transmitted on the path regardless of whether the path is switched.

In the above-described embodiments provided in the present application, various solutions of the transmission control method provided in the embodiments of the present application are described separately from the viewpoint of each network element and the interaction between the network elements. To implement the functions described above, it is understood that each network element, such as a session management function network element or a first user plane function network element, includes corresponding hardware structures and / or software modules used to perform each function. Can be. Those skilled in the art should readily recognize that the units and algorithm steps of the examples described with reference to the embodiments provided herein can be implemented by hardware or a combination of hardware and computer software. Whether the function is performed by hardware driven by computer software or by hardware depends on the design constraints of the specific application and technical solution. Skilled artisans can use different methods to implement the described functionality for each particular application, but implementations should not be considered beyond the scope of this application.

For example, when the above-described network element implements a corresponding function using a software module, the transmission control device may include a processing module 801 and a transmission module 802 as shown in FIG. 8. The device may be a session management function network element or chip.

In one embodiment, the device may be configured to perform the operation of the SMF in FIG. 4A or 4B or the session management function network element of FIG. 5 (eg, SMF). For example, the sending module 802, in the process of reassigning the first user plane function network element to the second user plane function network element, a plurality of anchor users for each session modification request of the plurality of session mediation requests. Each anchor user of the planar functional network element is configured to transmit to the planar functional network element. The session modification request includes information regarding the second user plane functional network element. The processing module 801 instructs only the first anchor user plane function network element of the plurality of anchor user plane function network elements to transmit the end marker using the transmission module 802; Or it may be configured to transmit the end marker using the transmission module 802 only to the first anchor user plane functional network element.

Optionally, the sending module 802 first transmits each first session modification request from a plurality of anchor user plane function network elements to each anchor user plane function network element other than the first anchor user plane function network element, It is then configured to send a second session modification request to the first anchor user plane functional network element. Therefore, the session management function network element only indicates to the anchor user plane function network element that updates the path last, to send the end marker. In this way, the end marker sent by the anchor user plane function network element that last updates the route is used to indicate that the packet transmission on the previous route is complete, which avoids data packet loss on the previous route and the user experience. Improves.

Optionally, after the sending module 802 transmits each session modification request from a plurality of anchor user plane function network elements to each anchor user plane function network element other than the first anchor user plane function network element, the processing module ( 801) is configured to use the transmission module 802 to direct the first anchor user plane functional network element to transmit the end marker, or to transmit the end marker to the first anchor user plane functional network element. For example, the processing module 801 is configured to instruct the first anchor user plane function network element to send an end marker, using a session modification request sent to the first anchor user plane function network element, or a session The modification request includes an end marker; Alternatively, the processing module 801 may be configured to instruct the first anchor user plane function network element to transmit an end marker, using the first message sent to the first anchor user plane function network element, or the first message to end Includes markers.

Optionally, processing module 801 is further configured to determine the first anchor user plane functional network element. For example, the first anchor user plane function network element includes a remote user plane function network element or a home user plane function network element.

In another embodiment, the device may be configured to perform the operation of the SMF in FIG. 6A or 6B or the session management function network element (eg, SMF) of FIG. 7B. For example, processing module 801 is configured to determine that the first user plane functional network element is to transmit and receive data packets of the first session on multiple paths. The transmitting module 802 is configured to transmit the first indication information to the first user plane functional network element, where the first indication information is used for determination of the first path, and to the first user plane functional network element, After receiving the first end marker on one path, the first end marker is instructed to be transmitted to the access network device, and the first path is a path for finally transmitting the end markers in a plurality of paths.

Accordingly, the session management function network element transmits the first indication information to the first user plane function network element. The first user plane functional network element sends the end marker to the access network device based on the first indication information after receiving the last transmitted end marker. In this way, the end marker sent by the anchor user plane function network element that last updates the route is used to indicate that the packet transmission on the previous route is complete, which avoids data packet loss on the previous route and the user experience. Improves.

Optionally, the first indication information includes the quantity information, and the quantity information indicates the quantity of the route for transmitting the end marker in a plurality of routes.

Optionally, the sending module 802 transmits the first indication information to the first user plane function network element in the process of inserting the first user plane function network element or in the process of reallocating the first user plane function network element. It is configured to.

Optionally, the transmitting module 802 is further configured to transmit the second indication information to the first user plane function network element, wherein the second indication information is a downlink of the first session in the first user plane function network element. Used for the detection of data packets. For example, the transmitting module 802 may transmit the second indication information to the first user plane function network element in the process of inserting the first user plane function network element or in the process of reallocating the first user plane function network element. It is configured to send to.

Optionally, for the third solution described above, the processing module 801 further determines that the third route is not switched in the plurality of routes of the first session, and uses the sending module 802 to end marker Or configured to transmit the third indication information to the anchor user plane functional network element corresponding to the third route, where the third indication information directs the anchor user plane functional network element to transmit the end marker on the third path. In other words, the end marker must be transmitted on the path regardless of whether the path is switched.

In any of the foregoing embodiments, the device may further include a receiving module 803. The processing module 801, the sending module 802 and the receiving module 803 of the device may further implement other operations or functions of the SMF or session management function network element in the above-described method, details of which are here again Not explained.

Another transmission control device may include a receiving module 901 and a transmitting module 903 as shown in FIG. 9. Optionally, the device further comprises a processing module 902. The device may be a user plane functional network element or chip. The device may be configured to perform the operation of the source I-UPF in FIG. 6A or 6B or the first user plane functional network element of FIG. 7A (eg, source I-UPF). For example, the receiving module 901 is configured to receive uplink data packets on a plurality of paths. The transmission module 903 is configured to transmit downlink data packets on a plurality of paths. The sending module 903 is configured to send the first end marker to the access network device after the receiving module 901 receives the first end marker on the first path. The first path is a path for finally transmitting end markers in a plurality of paths.

In this way, the first user plane functional network element sends the end marker to the access network device after receiving the last transmitted end marker. The end marker sent by the anchor user plane function network element that last updates the path is used to indicate that packet transmission on the previous path is complete. Thus, data packet loss in the previous path can be avoided, and the user experience is improved.

Optionally, the processing module 902 is configured to discard the second end marker after the receiving module 901 receives the second end marker on the second route in the plurality of routes.

Optionally, the receiving module 901 is further configured to receive the first indication information from the session management function network element, where the first indication information is sent to the first user plane function network element, the first end on the first path. After receiving the marker, it is instructed to send the first end marker to the access network device. For example, in the process of inserting the first user plane functional network element or the process of reallocating the first user plane functional network element, the receiving module 901 is configured to receive the first indication information from the session management functional network element do.

Optionally, the first indication information includes the quantity information, and the quantity information indicates the quantity of the route for transmitting the end marker in a plurality of routes. Optionally, the processing module 902 is configured to determine the first route based on the first indication information. For example, when the receiving module 901 receives an end marker of the same quantity as the number of routes for transmitting the end markers in a plurality of routes, the processing module 902 establishes a route for finally sending the end marker. It is configured to determine as the first route.

Optionally, the receiving module 901 is further configured to receive second indication information from the session management function network element. The processing module 902 is configured to detect a downlink data packet of the first session based on the second indication information, and determine the downlink data packet as an end marker based on the detection result. For example, in the process of inserting the first user plane functional network element or the process of reallocating the first user plane functional network element, the receiving module 901 is configured to receive the second indication information from the session management functional network element. do.

In addition, the receiving module 901, the processing module 902 and the transmitting module 903 of the device further include a source I-UPF or a first user plane functional network element (eg, source I-UPF) in the above-described method. Other operations or functions can be implemented, and details are not described herein again.

10 shows another possible schematic structural diagram of the transmission control device provided in the above-described embodiment. The device includes a transceiver 1001 and a processor 1002 as shown in FIG. 10.

For example, the processor 1002 may be a general purpose microprocessor, data processing circuit, application specific integrated circuit (ASIC), or field-programmable gate arrays (FPGA) circuit. The device may further include a memory 1003, for example, the memory is random access memory (RAM). The memory is coupled to the processor 1002 and is configured to store the computer program 10031 required by the device.

In addition, the transmission control method provided in the above-described embodiment provides a computer readable storage medium 1004 (eg, a hard disk), where the computer readable storage medium stores the computer program 10041 of the device. The computer program 10041 may be loaded in the processor 1002.

When the computer program 10031 or 10041 is executed in a computer (eg, the processor 1002), the computer can perform the above-described method.

For example, in one embodiment, processor 1002 is configured to perform the operation or function of the session management function network element (eg, SMF) described above. The transceiver 1001 is configured to implement communication between the device and each anchor user plane functional network element or other user plane functional network element or other control plane network element (eg, AMF).

In another embodiment, the processor 1002 is configured to perform an operation or function of the first user plane functional network element (eg, source I-UPF) described above. The transceiver 1001 is configured to implement communication between the device and the anchor user plane functional network element or session management functional network element (eg, SMF).

The processor configured to perform the transmission control device in the present application includes a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), It may be a field-programmable gate array (FPGA) or other programmable logic device, transistor logic device, hardware component, or any combination thereof. The processor may implement or execute various exemplary logic blocks, modules, and circuits described with reference to content provided in this application. The processor may also be a combination of processors that perform computing functions, eg, one microprocessor, or a combination of one or more microprocessors, or a combination of a DSP and a microprocessor.

The method or algorithm steps described with reference to the content provided in this application can be implemented by hardware, or by a processor by executing software instructions. The software instructions can include corresponding software modules. The software module may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable hard disk, CD-ROM or any other storage medium known in the art. For example, since the storage medium is coupled to the processor, the processor may read information from or write information to the storage medium. Of course, the storage medium may be a component of the processor. The processor and storage medium may be located in the ASIC. In addition, the ASIC can be located in a communication device. Of course, the processor and storage medium may exist as separate components in the communication device.

All or part of the above-described embodiments may be implemented using software, hardware, firmware, or any combination thereof. When software is used to implement the embodiments, the embodiments may be implemented in whole or in part in the form of computer program products. A computer program product includes one or more computer instructions. When computer program instructions are loaded and executed in a computer, a procedure or function according to an embodiment of the present invention is completely or partially generated. The computer can be a general purpose computer, a dedicated computer, a computer network, or other programmable device. Computer instructions can be stored on a computer readable storage medium or can be transferred from a computer readable storage medium to another computer readable storage medium. For example, computer instructions may be wired (e.g. coaxial cable, fiber optic or digital subscriber line (DSL)) or wireless (e.g. infrared, radio or microwave), web site, computer It can be transferred from a server or data center to another website, computer, server or data center, where the computer readable storage medium is connected to a computer or data storage device such as a server or data center integrating one or more usable media. Any media that can be accessed by the media can be used, such as magnetic media (eg, floppy disk, hard disk, or magnetic tape), optical media (eg, DVD), semiconductor media (eg, Solid State Disks (SSDs) and the like.

The objects, technical solutions and advantages of the present invention are described in more detail in the specific embodiments described above. It should be understood that the foregoing description is only specific embodiments of the present invention, and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement or improvement made based on the technical solution of the present invention falls within the protection scope of the present invention.

Claims (30)

As a transmission control method,
In the process of reassigning the first user plane function network element to the second user plane function network element, the session management function network element requests a respective session modification of a plurality of session medication requests. Sending to each anchor user plane function network element of a plurality of anchor user plane function network elements-each session modification request of the plurality of session mediation requests is information about the second user plane function network element Contains-; And
The session management function network element indicates only the first anchor user plane function network element in the plurality of anchor user plane function network elements to transmit an end marker, or the session management function network element A) transmitting the end marker only to the first anchor user plane functional network element;
Transmission control method comprising a. According to claim 1,
The session management function network element transmitting each session modification request of the plurality of session modification request to each anchor user plane function network element of the plurality of anchor user plane function network elements,
Transmitting, by the session management function network element, each first session modification request from the plurality of anchor user plane function network elements to each anchor user plane function network element other than the first anchor user plane function network element; And
After sending each of the first session modification requests, sending a second session modification request to the first anchor user plane functional network element
Including, transmission control method. The method according to claim 1 or 2,
The session management function network element directs only the first anchor user plane function network element in the plurality of anchor user plane function network elements to transmit the end marker, or the session management function network element indicates the end marker. Transmitting only to the first anchor user plane function network element,
After the session management function network element transmits the respective session modification request to each anchor user plane function network element other than the first anchor user plane function network element from the plurality of anchor user plane function network elements, the A session management function network element instructing the first anchor user plane function network element to send an end marker, or sending an end marker to the first anchor user plane function network element
Including, transmission control method. The method according to any one of claims 1 to 3,
The session management function network element directs only the first anchor user plane function network element in the plurality of anchor user plane function network elements to transmit the end marker, or the session management function network element indicates the end marker. Transmitting only to the first anchor user plane function network element,
Instructing the first anchor user plane function network element to send the end marker, using the session modification request sent to the first anchor user plane function network element, or the session management function network element-or the session The modification request includes the end marker-; or
Instructing the first anchor user plane functional network element to transmit the end marker using the first message sent to the first anchor user plane functional network element, or the first 1 message contains the end marker-
Including, transmission control method. The method according to any one of claims 1 to 4,
Determining, by the session management function network element, the first anchor user plane function network element.
Transmission control method further comprising a. The method according to any one of claims 1 to 5,
The first anchor user plane functional network element comprises a remote user plane functional network element or a home user plane functional network element. As a transmission control method,
A first user plane function network element transmitting and receiving data packets over a plurality of paths; And
After the first user plane functional network element receives a first end marker on a first path, the first user plane functional network element sends the first end marker to an access network device-the first path Is a path for finally transmitting end markers in the multiple paths −
Including, transmission control method. The method of claim 7,
The first user plane functional network element receiving a second end marker on a second path in the plurality of paths and discarding the second end marker
Transmission control method comprising more. The method of claim 7 or 8,
Receiving, by the first user plane function network element, first indication information from a session management function network element, wherein the first indication information is sent to the first user plane function network element to the first end on the first path; After receiving a marker, instruct to send the first end marker to the access network device-
Including, transmission control method. The method of claim 9,
The first user plane function network element, receiving the first indication information from the session management function network element,
In the process of inserting the first user plane functional network element or in the process of reallocating the first user plane functional network element, the first user plane functional network element is the first instruction from the session management functional network element. Steps to receive information
Including, transmission control method. The method of claim 9 or 10,
The first indication information includes quantity information, and the quantity information indicates the quantity of a route for transmitting the end marker in the plurality of routes. The method according to any one of claims 9 to 11,
Determining, by the first user plane function network element, the first path based on the first indication information.
Transmission control method further comprising a. The method of claim 12,
The step of determining, by the first user plane function network element, the first route based on the first indication information,
When the number of paths in which the first user plane functional network element receives each end marker is equal to the number of paths for transmitting the end markers in the plurality of paths, the end marker is last Determining a path for transmission as the first path
Including, transmission control method. The method according to any one of claims 7 to 13,
The data packets transmitted and received on the plurality of paths are data packets of the first session, and the method includes:
Receiving, by the first user plane functional network element, second indication information from the session management functional network element;
Detecting, by the first user plane function network element, a downlink data packet of the first session based on the second indication information; And
Determining, by the first user plane function network element, the downlink data packet as the end marker based on a detection result
Including, transmission control method. The method of claim 14,
The first user plane function network element, receiving the second indication information from the session management function network element,
In the process of inserting the first user plane functional network element or in the process of reallocating the first user plane functional network element, the first user plane functional network element is the second instruction from the session management functional network element. Steps to receive information
Including, transmission control method. As a transmission control method,
Determining, by the session management function network element, that the first user plane function network element transmits and receives data packets of the first session on a plurality of paths; And
Transmitting, by the session management function network element, first indication information to the first user plane function network element, the first indication information is used for determination of a first path and to the first user plane function network element , After receiving the first end marker on the first path, instructs the first end marker to be transmitted to an access network device, the first path being a path for finally transmitting the end marker in the plurality of paths -
Transmission control method comprising a. The method of claim 16,
The first indication information includes quantity information, and the quantity information indicates the quantity of a route for transmitting the end marker in the plurality of routes. As a transmission control device,
In the process of reassigning the first user plane function network element to the second user plane function network element, each anchor user plane function network of each anchor user plane function network element is requested for each session modification request of the plurality of session mediation requests. A transmitting module configured to transmit to an element, wherein each session modification request of the plurality of session mediation requests includes information regarding the second user plane functional network element; And
The sending module is configured to indicate only the first anchor user plane function network element in the plurality of anchor user plane function network elements to transmit end markers, or using the transmission module, the end marker is A processing module configured to transmit only to the first anchor user plane functional network element
Transmission control device comprising a. The method of claim 18,
The sending module first sends each first session modification request to each anchor user plane function network element other than the first anchor user plane function network element from the plurality of anchor user plane function network elements, and then And transmit a second session modification request to the first anchor user plane functional network element. The method of claim 18 or 19,
After the sending module transmits the respective session modification request to each anchor user plane function network element other than the first anchor user plane function network element from the plurality of anchor user plane function network elements, the processing module , Using the sending module, configured to instruct the first anchor user plane functional network element to transmit an end marker, or to transmit an end marker to the first anchor user plane functional network element. The method according to any one of claims 18 to 20,
The processing module instructs the first anchor user plane function network element to transmit the end marker using the session modification request sent to the first anchor user plane function network element-or the session modification request is the Includes end markers-constructed, or
The processing module directs the first anchor user plane function network element to transmit the end marker using the first message sent to the first anchor user plane function network element-or the first message is the Includes end markers-configured, transmission control device. The method according to any one of claims 18 to 21,
And the processing module is further configured to determine the first anchor user plane functional network element. As a transmission control device,
Receiving module; And
Send module
Including,
The receiving module is configured to receive uplink data packets on a plurality of paths, or the transmitting module is configured to transmit downlink data packets on a plurality of paths, and
The transmitting module, after receiving the first end marker on the first path, to transmit the first end marker to an access network device-the first path is a path for finally transmitting the end marker in the plurality of paths Im-configured, transmission control device. The method of claim 23,
A processing module configured to discard the second end marker after the receiving module receives the second end marker on the second route in the plurality of routes
Transmission control device further comprising a. The method of claim 23 or 24,
The receiving module further receives first indication information from a session management function network element-the first indication information receives the first end marker on the first path, and then accesses the first end marker Instructing the first user plane functional network element to transmit to a network device-configured, a transmission control device. The method of claim 25,
The first indication information includes quantity information, and the quantity information indicates the quantity of a route for transmitting the end marker in the plurality of routes. The method of claim 25 or 26,
A processing module configured to determine the first route based on the first indication information
Transmission control device further comprising a. The method of claim 27,
When the receiving module receives an end marker whose quantity is equal to the quantity of the route for transmitting the end marker in the plurality of routes, the processing module transmits the route for finally transmitting the end marker to the first route. A transmission control method, configured to determine as. The method according to any one of claims 23 to 28,
Further comprising the processing module,
The receiving module is further configured to receive second indication information from the session management function network element, and
And the processing module is configured to detect a downlink data packet of the first session based on the second indication information, and determine the downlink data packet as the end marker based on the detection result. As a transmission control device,
A processing module configured to determine that the first user plane functional network element transmits and receives data packets of the first session on the plurality of paths; And
Send first indication information to the first user plane functional network element-the first indication information is used for determination of a first route and after receiving a first end marker on the first route the first end marker Directs the first user plane functional network element to send to the access network device, the first path being a path for finally transmitting the end marker in the plurality of paths-transmitting module
Transmission control device comprising a.

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